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Calculating meteorological drought indices with embedded Middle-east database

This tool has been improved to Rain-based Drought Indices Tool from 2017-01-01 and you can use RDIT

What is MDM software?

We developed the "MDM" (Meteorological Drought Monitor) software application for calculating eight rain-based meteorological drought indices, namely: SPI (Standardized Precipitation Index), DI (deciles index), PN (Percent of Normal Index), RAI (Rainfall Anomaly Index), EDI (effective drought index), CZI (China-Z index), MCZI (modified CZI), and ZSI (Z-Score Index) in form of yearly, seasonally, monthly and moving average for 3, 6, 9, 12, 18, 24, and 48 months. Because using different drought indices at a given time can show drier or wetter than usual conditions (Smakhtin and Hughes, 2007), user-friendly software is a critical tool for calculating and comparing multiple locations, time periods, and data source influences efficiently. The “MDM” software package currently bases calculations on two sources of data. The first is a synoptic station data file, which includes daily precipitation in excel format. The second one is a database of daily precipitation from AgMERRA, available for the Middle-East region. The user can click the map on the desired point in the package and calculate all indices for that 0.25 degree grid location. There is a complete help file in the package, which describes all setup steps.

What is meteorological drought indices?

The Intergovernmental Panel on Climate Change (IPCC) AR4 (Fourth Assessment Report) has mentioned that, in general terms, drought is a prolonged absence or marked deficiency of precipitation, a deficiency of precipitation that results in water shortage for some activity or for some group or a period of abnormally dry weather sufficiently prolonged for the lack of precipitation to cause a serious hydrological imbalance.

The American Meteorological Society (AMS) (1997) separates drought into four categories: meteorological (lack of precipitation), agricultural (lack of root zone soil moisture), hydrological (drying of surface water storage), and socioeconomic (lack of water supply for socio-economic purpose) droughts. The standards for drought conditions are based on regional climatology. Normally, meteorological measurements are the first indicators of drought.

A meteorological drought can be seen as a result of a precipitation shortage or which is defined as the lack of precipitation over a region for a period of time. It is usually region-specific because the atmospheric conditions in different areas are highly variable in space and time.

Depending of the duration of meteorological drought, the soil humidity will be reduced (shorter term) and the groundwater table can be dropped (longer term). Meteorological drought is signaled by indicators intrinsic to weather data and precedes the onset of specific impacts, i.e. additional kinds of drought.

There are different indices for monitoring and assessing the amount of meteorological droughts. Through the rain-based meteorological drought, we can track the amount of drought just by precipitation’s value.

Watch Drought Course Videos: Drought Lesson

You can find sample of input data file in this link

If you face with problem in registration process, please send an email to to get registered version of software.